Tractors and utility vehicles used for agricultural work and lawn care may carry a mid-mounted implement such as a mower deck that covers two or more rotary cutting blades on the lower ends of vertically oriented spindles. The implement may be attached to a tractor or other vehicle with mechanical linkages that allow the implement to be carried at a range of different heights, and raised or lowered between each height. Suspension devices may provide a parallelogram linkage arrangement between the front and back portions of the implement and vehicle to assure that as the implement is raised or lowered, the sides, front and rear of the implement are lowered or raised equally. For example, U.S. Pat. Nos. 5,025,617 and 6,584,756 relate to parallelogram lift linkages for mid-mounted implements.
Mower decks, snow blowers, and similar implements are not utilized full time with a tractor, so it is desirable that a suspension mechanism allow quick, easy removal and reinstallation of the implement. A mid-mounted implement also must be carefully positioned under the tractor at a specified location where the implement may be connected to the lift system linkage and PTO coupling members. Various mounting points in the lift system linkage must be aligned, and a tractor PTO shaft may be connected and secured to a propeller shaft on the implement using PTO coupling members.
Connecting a mid-mounted implement may be difficult due at least in part to the weight of the implement and connection points of the lift system that must be aligned. Additional effort may be required to secure PTO coupling members together. Removing a mid-mounted implement from under a tractor also may be difficult for the same reasons.
An automatic connection mechanism is needed for an implement that can be quickly and easily connected and disconnected under a tractor. A PTO coupling is needed that can reduce the difficulty of securing a tractor PTO to a propeller shaft on the implement.